Investments (Net Investment Income) (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Net Investment Income [Line Items]
Gross investment income	$ 1,264	$ 928	$ 3,652	$ 3,197
Less: Investment expenses	90	71	271	161
Net investment income	1,174	857	3,381	3,036
Fixed maturity securities
Net Investment Income [Line Items]
Gross investment income	886	779	2,577	2,221
Equity securities
Net Investment Income [Line Items]
Gross investment income	1	1	2	2
Mortgage loans
Net Investment Income [Line Items]
Gross investment income	240	207	715	614
Policy loans
Net Investment Income [Line Items]
Gross investment income	11	10	33	31
Limited partnerships and LLCs
Net Investment Income [Line Items]
Gross investment income	52	(106)	128	257
Cash, cash equivalents and short-term investments
Net Investment Income [Line Items]
Gross investment income	50	17	133	22
Other
Net Investment Income [Line Items]
Gross investment income	$ 24	$ 20	$ 64	$ 50

Amount, before investment expense, of income earned from investments in securities and real estate. Includes, but is not limited to, real estate investment, policy loans, dividends, and interest. Excludes realized gain (loss) on investments.

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Amount, after investment expense, of income earned from investments in securities and real estate. Includes, but is not limited to, real estate investment, policy loans, dividends, and interest. Excludes realized gain (loss) on investments.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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